Products

ST-500 Microscopy Cryostat

Overview

The Janis ST-500 continuous flow cryostat has been specially designed for use in microscopy, imaging, and high spatial resolution photoluminescence. The combination of low thermal-expansion support structure and internal vibration isolation results in nanometer scale vibration and drift levels. The cryostat geometry offers a short working distance (for use with high magnification optics), and permits mounting on common microscope stages and translators.

Standard Configuration

The ST-500 system includes a flexible high-efficiency variable flow cryogen transfer line. This line delivers liquid helium or liquid nitrogen to a two-stage heat exchanger and sample mount. The ST-500 is portable, easily mounted in a variety of configurations, and can be used both in transmission and reflection geometries.

Close up of ST-500 sample mount area. Aperture size and sample distance are customer selectable.

Specifications

NOTE: Specifications do not include optical or experimental heat loads and assume horizontal orientation. Specifications may change depending on the length of the transfer line flexible section.† Vibrational amplitude measured while on isolated optical table.
Results may vary depending on experimental conditions.
‡ Data courtesy of B. B. Goldberg and M. S. Unlu, Departments of Physics,
ECE and Photonics Center, Boston University.

Long Term Drift Data

ST-500 long term drift data from University of Oxford, Janis Research, cryogenics

Data taken by K.H. Lee (University of Oxford)

The Taylor group at University of Oxford has performed some characterization of the ST-500 cryostat drift. The characterization is based on the tracking of a single QD over time, and test results indicate a typical positional drift of about 2 nm/min.

Displacement Chart

Other Configurations

Compact and Ultra-Compact Configurations
Compact and ultra-compact designs are also available if space restrictions do not allow the use of the ST-500. Click here for details on the ST-300-MS SuperTran cryostat. Click here for information on the ST-500-UC ultra compact cryostat.

Options for Micro-Spectroscopy Techniques
Special Diamond Anvil Cell (Diacell® CryoDAC-ST) configured for use with the ST-500 is available from easyLab Technologies Ltd. Click here for details.
Special Diamond Anvil Cell configured for use with the ST-500 is available from D'Anvils.Click here for details.

Nano-Positioning Stages from attocube
Nano-positioning stages can be installed on the ST-500 microscope cryostats for a number of short working distance applications. Because this design uses a standard ST-500 cryostat as a base, existing cryostats may be upgraded to the special attocube configuration. The photo on the far left shows an ST-500-attocube with a special flange mounted on the bottom that will interface with an optical table. From the outside, this special ST-500-attocube looks identical to the model ST-500-LGV microscopy cryostat, which has a 2.5 inch cold plate and 7 inch outer diameter vacuum chamber. Contact Janis for more information.

Special ST-500-LGV with 11 inch Diameter Vacuum Shroud
The customer-designed sample holder was very large so a large 11 inch diamter vacuum shroud was used.

Sample Extension for Magnetic Measurements
Using the same proven cryostat design as the regular ST-500 cryostat, the ST-500 for magnetic measurements features an extended sample mount for use inside the bore of a magnet. This extended sample mount may be purchased separately, or with a set of permanent magnets for measurements in fields of up to 0.5 T.

The photo to the right shows the ST-500 with extended sample mount and permanent magnet. The length of the extension may be specified at the time of ordering, and the position of the magnet relative to the sample is fixed using a Teflon spacer. The magnetic field direction is perpendicular to the plane of the sample.

The flexible ST-500 design means that the cryostat may be ordered with an extended sample holder and vacuum shroud for magnetic measurements, and a standard sample holder and vacuum shroud for other measurements. Switching between the two holders is as simple as changing samples.

A set consists of up to five interchangeable magnets: the full set allows measurements in discrete steps of 0.1 T. Existing ST-500 cryostats may be upgraded by simply ordering the special sample holder, vacuum shroud top plate and radiation shield cover.

Breakout Box Accessory for Electrical Measurements
For customers requiring multiple feedthroughs for electrical measurements, Janis can build a breakout box. The photo shown illustrates a special ST-500 with O-ring sealed top and bottom windows and breakout box.

Sample Extension and Breakout Box Accessory

O-ring Sealed Top and Bottom Windows
For customers who require soft windows that cannot be epoxy sealed, we offer the option of using an o-ring seal to install the windows. The lower window is recessed so that it is flush with the bottom surface of the cryostat. The photo shows a cryostat with o-ring sealed top and bottom windows. This cryostat also featured a breakout box.

ST-500 with Special NW-50 Top Flange
The photo to the right shows a model ST-500 with a special NW-50 top flange that will mate with a flexible bellows in the customer's existing equipment

ST-500 with Two Special Sample Holders and Black Anodized Aluminum Baseplate
The ST-500 shown has two special sample holders (DIP socket and special customer-design) and a black anodized Aluminum baseplate. The baseplate was designed to customer specifications so they can mount the ST-500 in their own set up. The ST-500 will be operated vertically. This baseplate design requires an adaptor flange. When the baseplate has clearance holes, instead of tapped holes, the customer can mount their ST-500 directly to the optical bench without providing any special hardware on their own.

Mounting Flange for Optical Table
This ST-500 includes a mounting flange to allow it to be bolted to an optical table.

Spare Top Plate
The photo to the right shows a spare top plate available as an accessory or upgrade for the ST-500 microscopy cryostat.

Special XY Manipulator Stage for Use with ST-500

Ultra High Vacuum ConfigurationsST-500-UHV cryostat for microscopy with a UHV sample environment.
This cryostat combines the already proven ultra-low vibration and thermal drift of the standard ST-500 microscope cryostat with UHV-compatible design features. This continuous flow cryostat includes the same heat exchanger design as the standard ST-500 resulting in a low thermal drift of ~2 nm/minute. It also has the same low base temperature (3.8 K) and helium consumption (~1.1 liters/hour) as the standard ST-500.

Fully bakeable to 175 °C (~450 K), this cryostat is true-UHV and is equipped with a viewport configured for short working distance measurements. Different window materials are available to suit the required transmission range. Depending on the window thickness, the working distance can be as short as 1 mm. Like the standard ST-500, this versatile design can be modified to accept internal nano-positioning stages for x-y-z motion. Systems incorporating nano-positioning stages utilize flexible UHV copper thermal braids for sample cooling. The cryostat can also be configured for reflection or transmission measurements, and includes electrical feedthroughs allowing a range of electrical measurements to be performed. The ST-500-UHV can be used with liquid helium or liquid nitrogen, and will operate in any orientation. Janis can supply a complete turn-key package, including temperature controller and pumping station. Contact Janis today to see how the ST-500-UHV can be tailored to meet your specific experimental needs.

Superconducting Magnet for High Resolution Microscopy
Designed to operate with a Janis high stability microscopy cryostat, this system allows microscopy measurements to be performed in fields of up to 6 T. The system comes with X-Y-Z translation stages for sample scanning and focusing, and is designed for magneto-optical imaging at helium temperatures. Click here for details.

Micro-Manipulated Cryogenic & Vacuum Probe Systems for Chips, Wafers and Device Testing
The Janis ST-500 series probe stations are high performance research instruments designed to provide affordable vacuum and cryogenic probing of wafers and devices. The proven ST-500 cryostat is the platform for these probe stations, and includes low vibration technology (originally designed for high spatial resolution optical microscopy) to provide outstanding sample positional stability. Researchers around the world are using these systems to conduct research in a wide variety of fields, including MEMS, nanoscale electronics, superconductivity, ferroelectrics, material sciences, and optics. Click here for details.